Human NTera2 teratocarcinoma cells were differentiated into postmitotic NT2-N neurons and exposed to hypoxia for 6 h. The cultures were evaluated microscopically, and percent lactate dehydrogenase (LDH) release after 24 and 46 h was used as an assay for cell death. After 48 h LDH release was 24.3 ±5.6% versus 13.8 ±3.7% in controls (p < 0.001). Cell death was greatly diminished by MK-801 pretreatment (15.4 ± 5.1%, p < 0.001). If glutamine was omitted from the medium, glutamate levels after 6 h of hypoxia were reduced from 101 ±63 to 2.3 ±0.3~tM,and cell death at 48 h was also markedly reduced (15.4 ± 4.5%, p < 0.001). The a-amino-3-hydroxy-5-methylisoxazole-4-propionate antagonist 6-cyano-7-nitroquinoxaline-2,3-dione (18.7 ± 5.1%, p < 0.001) and mild hypothermia (33.5-34°C) during hypoxia (19.5 ±2.7%, p < 0.05) were moderately protective. Basic fibroblast growth factor (24.1 ±3.2%), the nitric oxide synthase inhibitor N°-nitro-L-arginine methyl ester (22.8 ±8.1%), the antioxidant N-tert-butyl-o-phenylnitrone (18.9 ±5.9%), and the 21-aminosteroid U74389G (24.0 ±3.4%) did not protect the cells. N-Acetyl-L-cysteine even tended to increase cell death (30.1 ±2.5%, p = 0.06). Treatment with MK-801 at the end of hypoxia did not reduce cell death (23.3 ±2.3%). In separate experiments, a 15-mm exposure to 1 mM glutamate without hypoxia did not result in significant cell death (14.7 ±2.4 vs. 12.2 ±2.1%, p = 0.07). We conclude that, although somewhat resistant to glutamate toxicity when normoxic, NT2-N neurons die via an ionotropic glutamate receptor-mediated mechanism when exposed to hypoxia in the presence of glutamate. As far as we know, this isthe first reported analysis ofthe mechanism of hypoxic cell death in cultured human neuronlike cells.

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OBJECTIVES:In 2014, the American Academy of Pediatrics published bronchiolitis guidelines recommending against the use of bronchodilators. For the winter of 2015 to 2016, we aimed to reduce the proportion of emergency department patients with bronchiolitis receiving albuterol from 43% (previous winter rate) to ,35% and from 18% (previous winter rate) to ,10% in the inpatient setting.METHODS: A team identified key drivers of albuterol use and potential interventions. We implemented changes to our pathway and the associated order set recommending against routine albuterol use and designed education to accompany the pathway changes. We monitored albuterol use through weekly automated data extraction and reported results back to clinicians. We measured admission rate, length of stay, and revisit rate as balancing measures for the intervention. RESULTS:The study period included 3834 emergency department visits and 1119 inpatient hospitalizations. In the emergency department, albuterol use in children with bronchiolitis declined from 43% to 20% and was ,3 SD control limits established in the previous year, meeting statistical thresholds for special cause variation. Inpatient albuterol use decreased from 18% to 11% of patients, also achieving special cause variation and approaching our goal. The changes in both departments were sustained through the entire bronchiolitis season, and admission rate, length of stay, and revisit rates remained unchanged.CONCLUSIONS: Using a multidisciplinary group that redesigned a clinical pathway and order sets for bronchiolitis, we substantially reduced albuterol use at a large children's hospital without impacting other outcome measures.Bronchiolitis is 1 of the most common reasons for hospitalization in young children, accounting for 18% of hospital admissions for children younger than age 1 and $1.73 billion in hospital charges in the United States in 2009. 1 Bronchodilators are commonly used to treat children with bronchiolitis, although research has shown no benefit in respiratory status of inpatients, admission rate, or hospital length of stay. 2,3 In 2014, the American Academy of Pediatrics (AAP) updated their guidelines on bronchiolitis, recommending against treatment with bronchodilators. 3,4 One of the Society of Hospital Medicine's 5 opportunities for increasing value in health care is not using bronchodilators in bronchiolitis. 5 Despite the AAP guideline and meta-analyses recommending against the use of bronchodilators, this practice is common throughout pediatric institutions. 6,7